In electrophotography, a uniform electrostatic charge is initially applied to the surface of a photoconductive layer of a film element. This charge is then selectively dissipated in accordance with a particular pattern as determined by exposure of the photoconductive layer surface to a light image. The resulting charge pattern therefore defines an electrostatic latent image upon the photoconductive layer. This latent image may then be rendered visible by applying electrostatically charged toner particles to the photoconductive layer, the toner particles adhering to the photoconductive layer surface by means of electrostatic attraction. In turn, the visible image may now be rendered permanent by subjecting the toner particles to a heating process or treatment which fuses the particles to the photoconductive layer.
As is well-known, in accordance with the conventionally acceptable developing method utilizing a liquid developer or toner, which comprises a liquid carrier for finely divided electrostatic toner particles, such as, for example, carbon particles, suspended therein, the electrophotographic element or image-exposed film is initially dipped within the liquid toner so as to produce the visible image thereon which of course corresponds to the originally defined latent image. While this development method has of course proven to be quite satisfactory for some types of systems and film, it is simply not feasible or applicable for the specialized type of system in which the imaging and developing are to be automatically accomplished within a single piece of apparatus. A microphotographic reproducing machine in which data from successive documents is sequentially recorded upon individual portions or frames of a multi-frame microfiche is an exemplary embodiment of the aforenoted specialized type of apparatus.
In addition, in view of the fact that it is desirable to rapidly image and develop each frame prior to, or partially co-extensive with, the processing of the next succeeding frame, the image development process must, of necessity, be one which can be accomplished quickly and conveniently with respect to, for example, a microfiche, strip or roll film, or aperture card, fixed within a suitable holder or support means within the reproduction apparatus. In particular, the processing apparatus or system must be capable of quickly and compactly develop the imaged areas of the microphotograph, including the foregoing electrostatic charging of the microphotograhic image area, exposure of the image area, toning of the image area, and fusing of the image area. Still further, it is highly desirable for the transportation logistics of the film within the system to be simplified so as to achieve a unidirectional processing of the film and its imaged areas whereby the apparatus may be rendered compactly arranged, and the development time for the imaged area, as determined from the initial charging process step to the fusing step, is minimized. In addition, such logistics would also, in turn, permit simultaneous, or time-overlapping development of multiple images upon multiple image areas or frames of, for example, a microfiche, roll film, or the like.
Electrophotographic development apparatus for processing microfiche is currently commercially available as embodied within the System 200 record processor which is manufactured and distributed by A. B. Dick/Scott of South Hadley, Mass. This system is disclosed within U.S. Pat. No. 3,972,610 issued to Frank C. Gross. While this system is therefore appreciated as being commercially successful as a viable record processor apparatus, it is further appreciated that this system is quite complex and needlessly time-consuming in the development process of not only a single imaged area of a microfiche, for example, but also with respect to the imaging of a plurality of areas to be recorded upon the microfiche or other similar microformats.
In particular, for example, as may best be appreciated from FIG. 15 of U.S. Pat. No. 3,972,610, the development processing apparatus of the System 200 employs separate charge/expose, tone/dry, and fuse modules with respect to which the microfiche is reciprocatingly moved in order to accomplish the various processing steps inherent in the formation of the microfiche imaged areas. More importantly, the reciprocal movement of the microfiche is multi-directional in conjunction with the processing or development of a single imaged area or frame. This is due to the fact that the dry/fuse module is interposed between the charge/expose module and the tone/dry module. Consequently, the development process for a particular frame of the microfiche is quite time-consuming in view of the fact that the modules themselves have to be shifted toward and away from the fiche, and the fiche itself has to be reciprocated laterally in opposite directions in order to be properly aligned with the particular processing module. This lateral, multi-directional shifting of the microfiche relative to the various processing or development modules also prevents the simultaneous or overlapping processing of several microfiche image frames. To the contrary, a second image frame of the System 200 microfiche can only be imaged and developed after a first image frame has been completely imaged and developed. Consequently, the overall processing time for a complete microfiche is seen to be quite expensive.
A need therefore exists for an improved apparatus for imaging and developing electrophotographic microformats wherein the various processing components of the imaging and developing system are compactly arranged so as to reduce the overall size of the apparatus and the through-put processing or development time for a particular imaged area of a microfiche, roll film, or an aperture card. In addition, there is a need for providing such improved apparatus of the foregoing type wherein the movement or transportation of the electrophotographic film element is unidirectional so as to insure the minimization of the development or processing time for a particular imaged area of the film element, and to additionally permit the simultaneous processing of several imaged areas of the film element in a staggered time sequence.
Accordingly, it is an object of the present invention to provide a new and improved apparatus for imaging and developing electrophotographic microformats.
Another object of the present invention is to provide new and improved apparatus for imaging and developing electrophotographic microformats which overcomes the disadvantages and operational drawbacks characteristic of similar conventional apparatus which represents the state of the art of the current technology.
Still another object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats which can accurately, economically, and efficiently reproduce documentary material upon such electrophotographic microformats.
Yet another object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats which can accurately, economically, and efficiently reproduce documentary material onto selected areas of such electrophotographic microformats, such as, for example, a microfiche, aperture card, roll or strip film, or the like.
Still yet another object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the various processing components of the imaging and developing system are compactly arranged so as to reduce the overall size of the apparatus.
Yet still another object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the various processing components of the imaging and developing system are compactly arranged so as to substantially reduce the through-put processing or development time required for the complete reproduction of an original document image upon the particular area of the microformat element.
A further object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the movement or transportation of the microformat is unidirectional so as to insure the minimization of the development or processing time for a particular imaged area of the microformat or film element.
A still further object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the movement or transportation of the microformat or film element is unidirectional so as to facilitate the simultaneous processing or image development of multiple imaged areas upon the film element in a staggered time sequence.
A yet further object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats which can be manufactured substantially less expensively than the similar conventional apparatus which represents the state of the art of current technology.
A still yet further object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the apparatus is substantially simpler in its arrangement of its component parts requisite for the imaging and development of one or more predetermined areas or frames of the microformat film element as compared to the arrangement or disposition of the corresponding components of the conventional state of the art apparatus.
A yet still further object of the present invention is to provide a new and improved apparatus for imaging and developing electrophotographic microformats wherein the transportation logistics of the apparatus of the present invention are substantially simpler and able to be accomplished substantially faster than the corresponding logistics of the conventional state of the art apparatus.